I admit it's a bit unclear. I should update the infographics.
Here's a more detailed explanation of what each tea does.

Health Tea (Red)

Natural healing factor boosted to 102%
Injury healing factor boosted to 110%

+2% Blood filtration
+5% Blood pumping.

These stat boosts generally help pawns recover better from illness or wounds.

Hibernation Tea (Orange)

Hunger rate factor reduced to 15%
Rest fall factor (speed at which rest need falls) boosted to 320%

Consciousness limited to 60%

Purifying Tea (Yellow)

Removes any Hediffs that are currently in a life threatening stage (Does not include Broot Poisoning) and causes the pawn to vomit directly afterwards.

Depending on the tea's quality, it can cause Broot Poisoning or not. Base chance is 40%, and quality acts as a multiplier on such chance.
Awful quality: 1.95x
Poor quality: 1.3x
Normal quality: 1x
Good quality: 0.75x
Excellent quality: 0.52x
Masterwork quality: 0.27x
Legendary quality: 0.11x

Side note: Broot poisoning isn't lethal per se, but it has a very high chance of causing heart attacks.

Immunity Tea (Black)

Reduces a single immunizable Hediff's severity by 12% of its current severity.

Immunity gain speed boosted to 112%

Digestive Tea (Green)

Forcefully sets Food Poisoning severity to 15% (Recovering stage)
Reduces severity of drunkenness by 8%

If the pawn has gut worms, it adds an invisible Hediff that simply neutralizes its effects by providing stat boosts that compensate those diminished by gut worms.

Toxic environment resistance boosted to 105%
Toxic resistance boosted to 105%

+35% Metabolism.

Warmth Tea (Red and Yellow)

Hunger rate factor boosted to 105%

-12ºC Minimum comfortable temperature
-10ºC Maximum comfortable temperature

Rage Tea (Lilac)

At >33% severity.

Pain factor reduced to 45%
Melee hit chance boosted to 125%
Melee dodge chance boosted to 125%
Shooting accuracy reduced to 92%
Aiming delay factor boosted to 112%
Mental break threshold reduced to 53%

+22% Moving

At <33% severity.

Pain factor boosted to 115%
Mental break threshold boosted to 153%
Rest fall rate factor boosted to 166%

-5% Moving

Circulatory Tea (Purple)

Constantly reduces severity of heart attacks by 0.001% per tick.

+10% Breathing
+25% Blood pumping.

Edit: When I put "X boosted to, say, 120%" it means that the stat boosts by a factor of 120%, that means that if your pawn has any issues that make a stat normally be at, say, 80%, it won't be boosted to 120%, but instead at 120% of 80%, that is, 96%

Awesome, thank you for the clarified details! Hugely appreciate it!

The gut worms bit and the Purifying Tea's 'use at this range' thing was what was tripping me up most; I had always used it before stuff hit life threatening.

Again, thank you so much!